This invention relates generally to cushioning products for protecting during shipping an item packaged in a box or carton and machines for making same, and more particularly to an air pillow cushioning product and a machine for making such an air pillow.
In the process of shipping an item from one location to another, a protective packaging material is typically placed in the shipping carton or box, to fill any voids and/or to cushion the item during the shipping process. Some conventional protective packaging materials are plastic, for example expanded polystyrene, foam peanuts and starch peanuts. While these conventional materials seem to perform adequately as cushioning products, they are not without disadvantages.
The most serious drawback of these types of cushioning products is the mess that is tended to be made when unpacking a carton or box shipped with such loosefill as the cushioning material. The peanuts tend to be strewn about the unpacking area, requiring time intensive cleanup. Further aggravating matters, in the case of plastic peanuts, is the tendency of the plastic peanuts to cling to the item shipped in the box, to people, to clothing, to carpet and to other structures in the unpacking area, due to static electricity.
One proposed solution for overcoming the deficiencies of loosefill as described above is the Flo-Pak Pouch(trademark) marketed by Free Flow Packaging International, Inc. of Redwood City, Calif. The Flo-Pak Pouch(trademark) utilizes a cylindrical plastic sleeve which is filled with polystyrene loosefill and the ends of which are gathered and tied off to form a cylindrical shaped or xe2x80x9csausagexe2x80x9d shaped bag of loosefill. While the Flo-Pak Pouch(trademark) does prevent the mess described above caused by loosefill, it is not without its own drawbacks. For example, the Flo-Pak Pouch(trademark) is somewhat difficult to utilize when packing articles to be shipped, as the cylindrical shaped bags do not bend easily to conform about an article within a box. Furthermore, the Free Flow Packaging machine which makes the Flo-Pak Pouch(trademark) does not include any capability for producing a string of bags of loosefill interconnected end-to-end, i.e. the Free Flow Packaging machine has the capability for producing only individual filled bags.
It would be desirable to better harness such loosefill material for cushioning purposes to exploit the cushioning properties of such loosefill but at the same time to eliminate the drawback of the mess associated therewith, while at the same time solving the problems presented by the Flo-Pak Pouch(trademark).
To this end, the invention disclosed in application Ser. No. 09/065,221 filed Apr. 23, 1998, assigned to the assignee of the present invention and hereby incorporated by reference herein as if fully set forth in its entirety, provides a number of cushioning products utilizing loosefill yet which avoid the prior problem of mess associated therewith, and which also provide for convenient loading of the product to be shipped into a carton therewith. One such cushioning product comprises a bag filled with loosefill packing material. The bag has a length, a width and a thickness, with the length and the width being substantially greater than the thickness. The loosefill packing material may be plastic peanuts, for example expanded polystyrene peanuts, or starch peanuts. A filled bag of loosefill according to this invention is preferably generally rectangular when viewed in side elevation and in end elevation, to promote wrapping an item to be shipped. The bag, which preferably is made of plastic, or even transparent plastic, preferably allows air to escape from it. To that end, the bag preferably includes a number of small holes therein. By allowing air to escape a xe2x80x9cballoonxe2x80x9d effect of the bags is avoided and the cushioning effect derives only from the cushioning qualities of the loosefill, rather than the compressability of the air within the bag and/or the elasticity of the bag. The cushioning product of that invention may also comprise a plurality of bags filled with loosefill packing material, with the bags being connected end-to-end in a string. In that case, a web of preformed and interconnected bags is provided, and loosefill packing material is inserted into the bags which are then sealed.
The invention of application Ser. No. 09/065,221 thus provides the cushioning qualities of loosefill, for example plastic or starch peanuts, yet without the attendant difficulties associated therewith. In addition, the preferred geometry of the bags of loosefill provide for easy insertion into a shipping box or carton as well as wrapping around the item to be shipped.
One limitation of the invention of application Ser. No. 09/065,221, however, is that the length of the cushioning product is not readily varied since the length of the cushioning product is dependent upon the length of the preformed interconnected bags which are purchased in web form and loaded onto the machine in a roll. It would be desirable to be able to vary the length of cushioning product produced without having to remove the existing roll of bags of one length and replacing that roll of bags with another roll of bags of the desired length.
Another feature of the invention of application Ser. No. 09/065,221 is the provision of loosefill for filling the bags to provide cushioning capability. In some applications it might be desirable to do away with the loosefill if an acceptable cushioning product can still be produced.
One attempt at eliminating the web of preformed and interconnected bags in forming a product containing bag has been made by Dibipack of Italy. The Dibipack machine uses a sheet of plastic film which is unrolled off of a roll, is formed into a cylindrical container, is filled with product and is then sealed. That machine comprises a frame, a plastic sheet supply assembly mounted on the frame, a forming assembly mounted on the frame downstream of the plastic sheet supply assembly which forms the plastic sheet into a tube with the lateral edges of the plastic sheet overlapping, a pulling assembly mounted on the frame downstream of the forming assembly which pulls the plastic sheet from the plastic sheet supply assembly to and over the forming assembly, a first heat sealing assembly mounted on the frame downstream of the forming assembly which heat seals the overlapping lateral edges of the tube together, and a second heat sealing assembly mounted on the frame downstream of the first heat sealing assembly which transversely heat seals the tube at each end of the longitudinal heat seal formed by the first heat sealing assembly. This machine is limited, however, in that the first heat sealing assembly is comprised of a fixed length heat sealing bar which is movable into and out of contact with the overlapping lateral edges of the tube to longitudinally heat seal the overlapping lateral edges. Thus, a user is limited to the length of bag capable of being produced on this machine to multiples of the length of this longitudinal heat sealing bar. Stated differently, this machine provides no capability of forming a desired length of bag other than in a length equal to the length of the longitudinal heat sealing bar or multiples thereof.
The present invention is a machine for producing cushioning product which allows a user to select a length of product to be produced from a continuous plurality of selectable lengths. A user is not limited to the length of preformed interconnected bags, nor to the length of the longitudinal heat sealing bar and multiples thereof, as determining the length of cushioning product to be formed.
In one aspect of the present invention, a machine for producing cushioning product comprises a frame, a plastic sheet supply assembly mounted on the frame, a forming assembly mounted on the frame downstream of the plastic sheet supply assembly which forms the plastic sheet into a tube with the lateral edges of the plastic sheet overlapping, a pulling assembly mounted on the frame downstream of the forming assembly which pulls the plastic sheet from the plastic sheet supply assembly to and over the forming assembly, a first heat sealing assembly mounted on the frame downstream of the forming assembly which is selectively activatable to longitudinally heat seal the overlapping lateral edges of the tube together a selected length from a continuous plurality of selectable lengths, and a second heat sealing assembly mounted on the frame downstream of the first heat sealing assembly which transversely heat seals the tube at each end of the longitudinal seal formed by the first heat sealing assembly to thereby form an air pillow.
The forming assembly preferably comprises in combination a cylinder and a collar, the collar transitioning the plastic sheet from a generally planar configuration as the sheet is pulled off of the plastic sheet supply assembly to a generally cylindrical configuration about the cylinder.
The pulling assembly preferably comprises a pair of drive belts, one belt of the pair of belts being located on each lateral side of the tube, and each of the pair of drive belts drivingly engaging the tube.
The first heat sealing assembly preferably comprises a heated wheel which is selectively movable into and out of contact with the overlapping lateral edges of the tube to heat seal the tube overlapping lateral edges together.
The second heat sealing assembly preferably comprises a pair of heated movable bars, positioned transversely of the longitudinal axis of the tube, and which are movable from an inoperative position spaced apart fore and aft of the tube to an operative sealing position wherein the bars are moved together such that the fore and aft wall portions of the tube are heat sealed together.
The present invention also provides a method of making a cushioning product, as well as a cushioning product made by the method. The method comprises providing a plastic sheet with lateral edges, forming the plastic sheet into a tube with the lateral edges of the plastic sheet overlapping, selecting a length from a continuous plurality of selectable lengths along which to longitudinally heat seal the overlapping lateral edges of the tube together, longitudinally heat sealing the overlapping lateral edges of the tube together the selected length, and transversely heat sealing the tube at each end of the longitudinal heat seal to thereby form an air pillow.
The major advantage of the present invention is that a user may readily vary the length of cushioning product produced. The user is not limited to any predetermined bag length as when a web of such preformed bags is utilized, nor is a user limited to a discrete length by the length of a longitudinal heat sealing bar and multiples thereof. Rather, a supply of plastic sheet is fed into the machine of the present invention which has the capability of producing air pillows of continuously variable lengths. In addition, as the machine of the present invention produces sealed air pillows, loosefill is not required as the cushioning qualities of the air itself can be exploited. However, if desired, the peanut dispensing portion of the machine of application Ser. No. 09/065,221 can be incorporated into the machine of the present invention to produce a bag or a string of interconnected bags of loosefill packing material.
These and other advantages of the present invention will become more readily apparent during the following detailed description taken in conjunction with the drawings herein, in which: